Device for forming springs.



B. A. LITGHFIELD 1&2 L. ZIMMERMANN. DEVICE FOR FORMING SPRINGS.

APPLICATION FILED FEB.18,1914.

1,1 05,982, Patented Aug. 4, 1914.

3 SHEETS- $HEET l.

nnnnnnnnnnn nnnn I HVEHTOR5 WITHESSEID I TTORNEY B. A; LITOHFIELD & L. ZIMMERMANN.

DEVICE FOR FORMING SPRINGS.

APPLICATION IILED IEB 18,1914.

1 ,1 05,982. Patented Aug. 4, 1914.

5 HHHHHHHHHHH HHHHHHHHH HHHHHHHHHnn WITNESSES 9 IHvEHToRs WA 15M M flTTORHEY B. A. LITOHFIELD & L. ZIMMERMANN. DEVICE FOR FORMING SPRINGS.

APPLICATION FILED FBB.18,1914. 1,105,982 Patented Aug. 4, 1914.

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Y E E WITHESSES ($9M %m %N.W x f- BY W 16 W W BYRON A. LITGHFIELD AND LOUIS ZIMMERMANN, F PONTIAC, MICHIGAN.

DEVICE FOR FORMING SPRINGS.

Specification of Letters Patent.

Patented Aug. 4, 1914.

Application filed February 18, 1914. Serial No. 819,317..

' To all whom it may concern:

shape. The former block A may be of any Be it known that we, BYRON A. Lrrorr- FIELD and LOUIS ZIMMERMANN, citizens of the United States, residing at Pontiac, county of Oakland, State of Michigan, have invented a certain new and useful Improvement in Devices for Forming Springs, and declare the following to be a full, clear, and exact description of the same, such aswill enable others skilled in the art to which it pertains to make and use the same, refere ence being had to the accompanying drawings, which form a part of this specification. I

Our invention relates to improvements in mechanism for the manufacture of springs, especially springs for vehicles adapted to travel upon common roads as carriages, wagons, automobiles and the like, and it con: sists in the various arrangements and combinations hereinafter described and claimed.

In the drawings: Figure 1, is a plan view. of our improved arrangement and construction with the spring blank in place adapted to be shaped to its permanent form. Fig. 2, is a plan view of the same apparatus with the blank shaped upon Fig. 3, is'a cross section on the line XX of Fig. 2. Fig. 4., is a cross section on the line Y--Y Fig. 2.

Similar letters refer to similar parts.

In the manufacture of springs the usual mode of shaping them is -to create a former which in the apparatus we have devised is.

shown at A, B being a blank heated to the extent of destroying its elasticity so that when it is formed, it will retain its formed particular form desired for the s ring. In the block we have shown, the the type used quite extensively in'the manufacture of automobile springs. The blank B being adapted when 'formed to be the master leaf of the spring although it is obvious that other and shorter blanks can be formed upon the same former A to conform thereto. The master leaf usually contains eyes at the ends e e to take attaching bolts and thereby attaching them to clips which in turn are attached to axles or other supporting means. i

C is a plunger adapted to be operated longitudinally in the dlrection of the arrow by any convenient means, as a rotating cam, hydraulic press, or other equivalent means for forcing it up toward the former block the rods.

the former block.

orm is of- A, as shown in Fig. 2. Of course, the former block A and its support A are held rigidly upon any convenient means of suppart (not shown) so that the plunger C can be made to approach it to within any determinate distance.

The plunger G comprises a frame D hav- 1ng cross bars E E which carry slidably engaging therewith rigid stems F F of any convenient number and which in turn support plunger bars G G. The bars G G themselves are in turn attached to the rods F lines in Fig. 4, at g and are fastened therein by set screws g g. By means of the set screws the bars G may be adjusted with reference to the rods F. Surroundin the rods F are strong spiral springs S S %eing held therein by pins S S passing through 0 By this means the bars G are cushioned, they being yieldingly held by the springs S S. I

In addition to the bars G G we employ two heavier thrust bars H H pivoted ,at k it upon the'plun er C the pivot hole being elongated, as shown at h Fig. 3. These bars H H are backed up preferably by bowed springs so that they also can yield 1n their elongated pivot holes to a certain extent agalnst any pressure brought agarnst their outer ends. At the outer ends are ournaled a pair of rollers R R. These are really friction rollers and are adapted to be brought upon the outer edges of the bars H H may be used as a bolt for instance.

at T Fig. 4.

It is in the use of the bars H connected by the spring S and their mode of operation, especially in regard to the forming of a spring of the form shown in the drawings that our invention more particularly resides. A larger number of plungers G, G may be used than are necessary ordinarily but these accommodate longer or shorter springs and also when not impinging upon any spring, theyoperate as guides for the other plungers. Ordinarily the plungers G G are set upon the rods F so that their by being counterbored, as shown in dotted simple.

lower ends. in contour generally conform to the shape of the form spring. This adjustment is made by the set screws 9 and when once set it is unnecessary to reset except a 5 new formerof different shape is employed rollers R R engaging that part of the spring which is opposite the concavities or reentering anglesnzz a .onthe former and bring mg a pressure to bear not only directly against the former but by virtue of the conmeeting spring S the pressure is on converging lines thus compelling the spring blank B to take the form of the concavity a a; The outer ends of the bars H H being separatedagainst the spring S the rolls R'R 11mg along the spring blank and rolling it into-shape, as it were, upon the former A. The plungers G G respectively also engage the spring-leaf and press closely into shape to the former A and when so pressed it is allowed to remain until the spring-leaf is comparatively cold when it sets in the form that it has been shaped to. The plunger head C carrying all these -attachments is then withdrawn, the formed spring-leaf may or may not be withdrawn as other and shorter leaves may be formed upon it using it as a former or it may be withdrawn and the shorter leaves forming upon the original former A if desired. .It is preferable, however, to form the leaves corresponding to the entire-spring upon one another successively as thereby their contours enlarge to conform to the enlargement required by the shape of the spring when assembled. Thus two to 45. four'or five successive leaves of the entire spring may be formed one after another,

each succeeding one being upon the one preceding it, until the entire assembled'spring is complete. The leaves thenare taken off,

heated and tempered in the usual manner.

Having thus described our invention what we desire to claimv is: e v

1, In mechanism of the class described,

'the combination of a former provided with a rentering angle, a plunger, a thrust bar having a sliding and pivoting movement on said plunger, a spring for normally thrusting the thrust bar on its sliding pivot toward the I former, and means for yieldingly pulling the thrust bar to the side of a line parallel with the line of travel of the plunger and toward the high side of the rentering angle of the former.

2. In mechanism of the class described, the combination of a former provided with a reenteringangle, a plunger adapted to be reciprocated toward and away from the former, a thrust bar having aslot and pin pivoting on. said plunger, a bowed spring carried on the plunger and engaging with the. pivoted end of the thrust bar, and a spring for yieldingly pulling the thrust bar toward the high side of the reentering angle of the former.

3. In mechanism of the class described,-

the combination of a former provided with reentering angles on eachside of its mid portion, a'plunger adapted to be reciprocated toward and away from the former, a pair of thrust bars having a sliding and pivoting'movement on said plunger on opposite side of the mid portion of the former with .one thrust bar in adjacency with each reentering angle, means for yieldingly forcing each thrust bar longitudinally toward the former, and means for yieldingly connecting the two thrust bars to .make them initially converge toward the mid portion of the former.

4. In mechanism of the class described,

the combination of a former having reentering angles in either side of the mid portion, a pilunger adapted to be reciprocated toward an yieldingly pressed plunger bars mounted upon the plunger and yieldingly tending in away from the former, a plurality of the direction of the former, a pair-ofthrust bars having a sliding and pivoting movement to the plungerand located onopposite sides of the mid portion of the former in adjacency one with each reentering angle,

the said two thrust bars being separated by I a plurality of. plunger bars, means for yield- .ingly thrusting the thrust 'bars'longitudinally toward the former, and means for yieldingly causing the thrust bars to initially converge, each bar tending toward the high side of the reentering angle.

In testimony whereof, we sign this specification in the presence of two witnesses.

BYRON A. L'ITCHFIELD. LOUIS ZIMMERMANN.

Witnesses:

FRANK F. GRIMMELSMAN, HAZEL M. JAY. 

